1. Field of the Invention
This invention relates to a class of machine elements and mechanisms that include gearing for the transmission of motion between a belt and a sprocket. More specifically, this invention pertains to a geared belt for the positive transmission of motion between the belt and a sprocket.
2. Description of the Prior Art
A non-articulated, geared, metal belt is disclosed by U.S. Pat. No. 2,971,392. This belt is formed by a continuous, load carrying, metal band with inflexible teeth in repeating spaced apart relationship and thin flexible portions bridging the space between successive teeth. At the junctures between the side faces of the teeth and the relatively thin sections between teeth are fillets of metal that provide a variable stiffness between the inflexible teeth and the thin flexible sections. These fillets increase the resistance to sharp bends in the metal band. Such bending is likely to produce permanent deformations or strains in the metal.
U.S. Pat. No. 3,636,788 teaches prestressing the links of a drive chain, at a crotch region between the inside flanks of the teeth, to provide a favorable residual compressive stress and thereby increase fatigue resistance. This prestressing is induced by a cold-forming operation. U.S. Pat. No. 239,114 shows metallic belting that has been bent to provide concave grooves or channels, extending transversely across the outer surface of the belting, and to present convex projections or arch shaped teeth upon the inner surface of the belting. These teeth engage grooves or furrows in the faces of pulleys. Such belting is used for applications where the work to be performed is very light, because tension in the belting would tend to straighten out the concave channels and reduce the projection of the arch shaped teeth. U.S. Pat. No. 2,711,815 shows belting with transverse crimps or corrugations that provide for expansion and contraction of the belting to withstand a wide range of temperature variation.